Related factors affecting the activity of enzyme preparations

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Enzyme preparations are a type of biological preparations that are more and more widely used. In addition to the biological field, they are also used in chemical synthesis, food processing, cosmetics and skin care, pharmaceutical synthesis, new materials, and environmental management. Among them, the activity of enzyme preparations determines The key factor of enzyme quality.


Enzyme preparation is a special protein preparation, so its function or effect is directly affected by environmental conditions. When the conditions are not met, its activity is greatly affected, or even completely ineffective. The activity of enzyme preparations is also a decisive factor in the price of their products, which are usually priced by enzyme activity, and only a few are weighed.


Enzyme activity is related to buffer, temperature and substrate

1. The effect of system pH on enzyme activity

Each enzyme has its suitable pH value. When other conditions remain unchanged, the pH value when the enzyme-catalyzed reaction rate is greater. In order to maintain the pH value of the enzyme-catalyzed reaction system and maximize the effect of the enzyme, a suitable biological buffer must be added to the system.

2. The influence of temperature on enzyme activity

The catalytic activity of the enzyme also requires a suitable temperature, otherwise the activity of the enzyme will be greatly reduced, and too high temperature may even change the protein structure of the enzyme, and the denaturation of the enzyme may cause permanent inactivation.

3. Isoelectric point of enzyme

The isoelectric point is the pH value when the surface of a molecule is not charged. For enzymes, the charge of the zwitterion varies with the pH value of the solution. When the positive and negative charges of the zwitterion are equal, the pH value of the solution is the same. Isoelectric point. The isoelectric point of an enzyme is the pH value when the positive and negative ion charges of the solution are equal. It is a different concept from the optimal pH value of the enzyme, but there is a correlation. The two values ​​are usually close or equal.

4. The Michaelis constant of enzymes

The Km value of an enzyme, the Michaelis constant, refers to the concentration of the substrate when the enzymatic reaction reaches half of the maximum speed Vm. It is only related to the structure of the enzyme and the substrate catalyzed by the enzyme, and has nothing to do with the concentration of the enzyme. The smaller the Michaelis constant, the better the affinity between the enzyme and the substrate. The minimum substrate is the natural substrate or the most suitable substrate for the enzyme. The substrate concentration can be calculated based on the reaction rate or the reaction rate can be calculated based on the substrate concentration.


It can be seen from the above that the factors affecting the activity of enzyme preparations include pH, temperature and the substrate of the enzyme. Among them, Desheng provides enzyme preparations, Tris, Bicine, CAPS and other buffers that maintain the optimal pH, and Trinder's chromogen substrate used in enzyme-linked immunoassay such as TOOS and MAOS.